Cerberus has been shown to be very loyal and close to his friends and masters. While his original master was Zeabolos, he was ordered by Zeabolos to stay with Elma at all times and, as a product of that, they have gotten inseparable. Despite his intelligence, he is still in essence, a dog and cannot ignore his baser instincts, e.g., fetching after thrown balls, his love for steak, and even his steadfast protectiveness.